Roots-style blower with leakage mechanisms

摘要

The disclosure concerns a Roots-type blower comprising a housing defining first and second transversely overlapping cylindrical chambers and at least one inlet port and an outlet port; first and second meshed, lobed rotors, each lobe having a top land sealingly cooperating with the cylindrical chambers; a plurality of control volumes for transfer of fluid, each control volume being defined by a pair of adjacent lobes on one of the rotors, and at least one of the cylindrical chambers; and blowholes formed within the cylindrical chambers in connection with meshing of the lobes of the first and second rotors. The blower further comprises at least one backflow slot extending through the housing wall of each cylindrical chamber for effecting a leakage of fluid from downstream the at least one outlet port into a control volume.